I had enough memories of maggots crawling over one of our cars when we tried to bring the garbage to the dumps. I would be more morose if I find maggots again in a food tub. I had a food tub filled with maggots ages ago because I forgot where I placed a food container and I barely remember that.

I used flies though. Penguin tetras along with the green aro love them.;)

I'm ready for the pressure.
The drama and the pleasure!If there is one thing I want to see here, it's HUMOR.I believe I can fly!
I believe I can touch the sky!
I think about it every night and day!I stand in awe of my body.

I am NOT a maggot person, but the only danger I can see with getting them from a tackle shop is that some are dyed. So the contents of the dye maybe damaging and also what they are fed upon may arise some concern, but that's just my opinion.

mealworms are beetle larva that are a pest in grain stores there very hard shelled so only feed them to fish with teeth
big maggots are bred on animal carcass waste there nutritional and soft bodied i personally wouldn't stick my hands in a tub of them they come in many different sizes due to species ranging from tiny fruit fly maggots up to the large horse fly type the dyed types are not harmful as the dyes are food type dyes that are commercial safe

As long as the maggots are washed well. I have fed fruit fly maggots to my fish in the past and they love them. I wouldn't feed them too often thought because they can be very fatty and will make your fish overweight.

Mealworms are the larva of the darkling beetle. Their scientific name is Tenebrio molitor and there are a couple others species, king mealworms and confused flour beetles. The kings are huge and the confused flour beetle is the smallest and easiest to raise and feed to your fish. Most fish will not eat the beetle unless you have a large oscar or arowana. Pond goldfish will eat them from what I have heard.

Fruit fly larva are easy to culture and will be high in vitamins depending on what you use for media to culture them.

The only thing I can see being a potential problem is the fact that bottle fly maggots are most often cultured in manure and it could contaminate the aquarium over time. Muska domestica is the common house fly and can be cultured the same as fruit flies although much less productive.